Mounting means for contact members



Jan. 27, 1959 C. J. MAHLER EI'AL MOUNTING MEANS FOR CONTACT MEMBERS F Filed Nov. 21, 1956 wrrmzsszs MR.G

A TORNEY aw 7%- A W United tes Patent p Ralph B. Immel, Williamsville, N. Y., assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application November 21, 1956, Serial No. 623,566

3 Claims. 01. 200-166) normally open or front contacts and normally closed or back contacts. The auxiliary contacts are utilized in control and indicating circuits of the system in which the device is connected. A device may be supplied with one or more sets of each type of contact depending on the requirements of the system in which it is utilized.

Sometimes it is necessary to change the auxiliary contacts from one type to the other in accordance with changes made in the system.

The means previously utilized for mounting auxiliary contact members required separate clips, screws, lock washers and nuts which had to be stocked and frequently became lost during maintenance. Also, the installation of the parts previously utilized required considerable space, decreased the electrical insulation distances and increased the cost of the device.

6 An object of our invention, generally stated, is to provide 'a simple'and improved means for mounting contact members on switching devices and relays.

A more specific object of our invention is to provide a means for mounting auxiliary contact members which permits the contact members to be readily changed from one type to another type.

A furtherobject of our invention is to provide aself-locking guide member for supporting contact members on a switching device.

Another object of our invention is to provide a contact guide member which compensates for manufacturing variations in the guide and its supporting member.

Other objects of ourinvention will be explained fully hereinafter or will be apparent to those skilled in the art.

In accordance with one embodiment of our invention, a bridging member, which spans a pair of stationary spaced contact members, is reversibly mounted on a guide membercomposed of a resilient material and has'a bifurcated end which extends through an opening in the cross bar of a contactor. The prongs of the guide member are pressed together while being forced through the opening and they spring apart after passing through the opening. The prongs have projections on their outer edges with sloping surfaces which engage the bottom of the opening to secure the guide member'in the cross bar. The bridging member may be reversed to change from a normally open to a normally closed type of auxiliary contact, or vice versa, by interchanging a spacing sleeve and a spring on the guide member.

For a better understanding of the nature and objects of the invention, reference may be had to the following of a bracket 21.

2,871,322 Patented Jan. 27, 1959 detailed description, taken in conjunction with the accompanying drawing, in which:

Figure 1 is a view, in perspective, of a normally open contact assembly embodying the principal features of the invention;

Fig. 2 is an exploded view, in perspective, of certain parts of the assembly shown in Fig. 1;

Fig. 3 is an enlarged section, in perspective, of a portion of the structure shown in Fig. 1;

v Fig. 4 is a view, in perspective, of a normally closed contact assembly;

Fig. 5 is an enlarged view, insection, showing the guide member partly inserted in the opening in the carrier or cross bar of a contactor;

Fig. 6 is an enlarged view, similar to Fig. 5, showing the guide member fully inserted in the cross bar, and

Figs. 7 and 8 are enlarged views, similar to Figs. 5 and 6, respectively, illustrating a modification of the guide member.

Referring to the drawing, and particularly to Fig. 1,

the normally open auxiliary contact assembly shown therein comprises a carrier or cross bar 11, only a portion of which is shown, a pair of spaced stationary. contact members 12 and 13 which may be mounted on a relay or contactor (not shown), a bridging member 14 having contact members 15 and 16 thereon for engaging the stationary contact members 12 and 13, respectively, a

guide member 17 for supporting'the bridging member 14, and a spacing sleeve 18 and a spring 19 disposed on the guide member 17 at opposite sides of the bridging member 14. The carrier or cross bar 11 may be molded from any suitable insulating material and it may be utilized for supporting main contact members of the relay or contactor as well as other auxiliary contact members in addition to those shown. The carrier 11 may be attached to the actuating means for the contactor by means Thus, the auxiliary contact members are actuated in conjunction with the main contact members of the relay or contactor.

As shown, a recess 22 is provided in one corner of the carrier 11. A raised portion 23 is provided on the top of the carrier 11 over the recess 22. As shown more clearly in Fig. 3, a generally rectangular opening 24 extends through the raised portion 23 into the recessed portion 22 of the carrier. As also shown in Fig. 3, the

contact guide 17 has a generally rectangular portion 25 which is disposed in the opening 24. The lower end of the guide 17 is bifurcated and each prong 26 has an angularly disposed projection 26 thereon; The upper surface of the projection 26 is preferably at an angle of approximately 30 to the surface of the carrier 11 which it engages at the bottom of the opening 24. The guide 17 has a shoulder 27 which engages the top surface of the raised portion 23 at the top of the opening 24. Thus, the guide member is wedged in the opening 24 and is held securely in place.

The guide member 17 is preferably molded from nylon which, in addition to being a good electrical insulator, also has exceptional wearing qualities and resilience. The resilient property of nylon is utilized to secure the locking action to retain the guide member, in the carrier 11.

As shown in Fig. 5, the guide member 17 may be pushed or driven into the opening 24 in the crossbar 11. The projections 26' engage the sides of the opening and the two prongs 26 of the bifurcated end of the guide 17 are pressed together while it is being inserted in the opening.

As shown in Fig. 6, when the guide member 17 is fully inserted in the opening 24 with the shoulder 27 engaging the top of the carrier 11 the projections 26 have passed through the opening 24 and the sloping surfaces of these 3 projections engage the carrier at the bottom of the opening 24. The prongs 26 have sprung apart because of the resilience of the material of which the guide member 17 is composed. However, the prongs 26 are not completely unrestrained because the sloping surfaces of the projections 26' engage the corners. of the carrier 11, thereby causing a wedging action. The wedging action between the projections 26 and the carrier 11 compensates for any clearance between the guide member 17 and the carrier 11 resulting from manufacturing variations. Thus, the guide member is held securely in the carrier 11. If it is desired to remove the guide member 17, it may be forced upwardly by means of a screw driver or other suitable tool placed between t.e lower end of the guide member and the bracket 21 which supports the carrier.

As shown more clearly in Fig, 2, the guide member 17 has an integrally formed head 28 on its upper end. As shown in Figs. 1 and 2, a spacing sleeve 18 is disposed on the guide member, between the head 28 and the bridging member 14- which is slidably disposed on the guide member. A spring 19 is disposed on the guide member between the bridging member 14 and the top surface of the raised portion 23 of the carrier 11. When the carrier 11 is moved vertically, the contact members 15 and 16 engage the stationary contact members 12 and 13, respectively, and the spring 1? is compressed to maintain a predetermined contact pressure between the contact members.

The contact assembly shown in Fig. 4 is of the normally closed type. It is similar in structure to the assembly shown in Fig. 1. However, the bridging member 14 is reversed and placed above the stationary contact members 12 and 13. The spacing sleeve 18 and the spring 19 are interchanged, the spring 19 being between the bridging member 14 and the head 28 of the guide 17, and the spacing sleeve 13 being between the bridging member and the raised portion 23 of the carrier 11. The contact members 15 and 16 engage the contact members 12 and 13 when the carrier 11 is in its lowermost position and are disengaged from the contact members 12 and 13 when the carrier 11 is raised vertically by the actuating means of the contactor.

As explained hereinbefore, it is sometimes necessary to change the auxiliary contact members on a device after it is originally assembled and installed. In the present structure, this may be readily accomplished by removingthe guide member 17 from the carrier 11 in the manner explained hercinbefore, reversing the bridging member 14, interchanging the sleeve 18 and the spring 19, and then reinserting the guide 17 in the carrier 11 in the manner previously explained. Thus, a contact assembly may be changed from a normally opened to a normally closed type, or vice versa. As previously explained, there are no small parts such as screws, clamps, lockwashers, and. nuts which frequently become lost or misplaced during maintenance operations.

The guide member 17', shown in Figs. 7 and 8 is similar to the guide member 17 with the exception that one of the prongs designated by the reference character 29 is straight and has no projection 26' thereon. The straight prong 29 engages the side of the opening 24 and a portion of the side of the recess 22 in the base 11, thereby providing more bearing surface for the guide member 17'. The wedging action is secured by the projection 26' on one prong only. The guide 17' may be inserted in the base 11 in the manner hereinbefore described. Also, it may be removed in the manner hereinbefore described.

From the foregoing description, it is apparent that we have provided a simple and efficient means for mounting auxiliary or other contact members of a relay or other electrical device. The contact members may be readily changed from one type to another and the possibility of losing parts of the structure during the maintenance operations is minimized. Furthermore, the apparatus is, safer electrically as the insulation and creepage distance between energized parts is greatly increased.

Since numerous changes may be made in the above described construction and different embodiments of the invention may be made without departing from the spirit and scope thereof, it is intended that all the matter contained in the foregoing description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

We claim as our invention:

1. In a contact assembly, in combination, a pair of spaced stationary contact members, each contact member having contact surfaces on opposite sides thereof, a bridging member having spaced contact members thereon for engaging the contact surfaces on one side of said stationary contact members when disposed at one side of the stationary contact members, a movable carrier having an opening therein, a bifurcated guide member extending through said opening, at least one of the prongs of the guide member having an angularly disposed projection thereon engaging the carrier at the bottom of said opening, to releasably retain the guide member in the opening, said bridging member being reversibly mounted on the guide member above the carrier, a spacing sleeve disposed on the guide member at one side of the bridging member, and a spring disposed on said guide member at the opposite side of the bridging member, said spring and said spacing sleeve being interchangeable on the guide member to change the location of the bridging member from one side of the stationary contact member to the opposite side to engage the contact surfaces on the opposite sides of the stationary contact members.

2. In a contact assembly, in combination, a pair of spaced stationary contact members, each contact member having contact surfaces on opposite. sides thereof, a bridging member having, spaced contact members thereon for engaging the contact surfaces on one side of said stationary contact members when disposed at one: side of the stationary contact members, a movable carrier having an opening therein, a bifurcated guide member extending through said opening, at least. one of the prongs of the guide member having an angularly disposed projection thereon engaging the carrier at the bottom of said opening to releasably retain the guide member in the opening, said'bridging member beingslidably and reversibly mounted on the guide member above the carrier, and a spacing sleeve and a spring disposed. on the guide member at opposite sides of. the. bridging member, said spring and said spacing sleeve being inter changeable on the guide member to change the location of the bridging member from one. side of the stationary contact member to the opposite side to engage the contact surfaces on the opposite sides. of thestationary contact members.

3. In a contact assembly, in combination, a pair of spaced stationary contact members, each contacttmemher having contact surfaces on opposite sides thereof", a bridging member having spaced. contact members thereon for engaging the contact surfaces on one side of said stationary contact memberswhen disposed at one side of the stationary contact members, a movable carrier having a generally rectangular. opening. therein, a bifurcated guide member having a generally rectangular portion extending through said opening, a shoulder on the guide member engaging the carrier at the top of said opening, at least one of the prongs of the guide member having an angularly disposed projection thereon engaging the carrier at the bottom of said opening to releasably retain the guide member in the opening, said bridging member being reversibly mounted on the guide member above the carrier, a spacing sleeve disposedon the' guide member at one side of the bridgingmember, and a spring disposed -on said guide member at theoppositeside of the bridging member, said spring and said spacing sleeve beingjnterchangeable on the guide member to change the location of the bridging member irom one side of the stationary contact member to the opposite side to engage the contact surfaces on the opposite sides of the stationary contact members.

References Cited in the file r this patent UNITED STATES PATENTS Goetz Dec. 29, 1931 Schleicher Dec. 30, 1947 

